Trematodes And Cestodes

Question 0

What group of animals are the final and intermediate hosts of digenetic trematodes

Answer 0

Vertebrate final host

Mollusk intermediate host - snail

Question 1

Characteristics of digametic trematodes

Answer 1

Covered with syncytium
Typically hermaphroditic
2 suckers, anterior and a posterior
All lay eggs

Question 2

What developmental stages found in the snail

Answer 2

Sporocysts
Daughter sporocysts
Redia
Cercaria (infective to vertebral host)

Question 3

Characterize trematodes transmission

Answer 3

With exception of schistosomes, all transmission of trematodes is via ingestion of the Cercaria stage

Question 4

Which flukes are transmitted via ingestion of vegetation

Answer 4

Fasciolopsis buski - giant intestinal fluke
Fasciola hepatica - sheep liver fluke
Fascioloides magna
Peramphistomes

Question 5

What are the vertebrate hosts of Fasciolopsis buski

Answer 5

Pigs and humans (small intestine)

Question 6

How are people infected and affected by Fasciolopsis buski

Answer 6

Peeling water chestnuts and buffalo nuts with their teeth - ingest metacercarial cyst
Usually no damage with small infections… May see edema of face, intestinal obstruction

Question 7

In what specific site are Fasciola hepatica found

Answer 7

Bile duct of sheep and cattle

Question 8

What causes disease in Fasciola hepatica infection

Answer 8

Larvae leave ingesting, come out through wall, burrow through liver to get to bile duct

Question 9

Distinguishing feature about Fasciola hepatica cercaria

Answer 9

They have a tail

Question 10

What site specific place are Fascioloides magna found I

Answer 10

Cysts in liver of white tailed deer

Question 11

How do Fascioloides magna affect sheep cattle and bison

Answer 11

Sheep - leave dark pigment when destroying liver
Cattle - do not find eggs in feces
Bison - refractory to infection

Question 12

How do peramphosomes cause pathology

Answer 12

Immature flukes burrow into wall of small intestine effort making their way back to the rumen where they live (or cecum/colon in hind gut fermenters)

Question 13

Which trematodes are transmitted via ingestion of insects

Answer 13

Dicrocoelium dendriticum - lanceolate liver fluke

Eurytrema pancreaticum/procyonis

Question 14

What vertebrates can Dicrocoelium dendriticum be found in, and in what organ
What insect must be ingested

Answer 14

Sheep, deer, woodchucks, cattle, pigs
Bile duct
Ants

Question 15

What age range of animals are pathological with Dicrocoelium dendriticum infection

Answer 15

Older animals, must be within animals for a ling time to see pathology

Question 16

Which trematodes are transmitted via consumption of crayfish and crabs

Answer 16

Paragonimus kellicotti

Question 17

In what hosts and where within the hosts do Paragonimus kellicotti live

Answer 17

Mink and bobcats naturally, also can infect dogs and cats

Live in cysts in the lungs (larva migrate straight throughout diaphragm to lungs)

Question 18

Which trematodes transmitted via ingestion of fish

Answer 18

Nanophyetus samlincola
Clonorchis sinensis
Opisthorchis
Metorchis

Question 19

What hosts are adult Nanophyetus salmincola found in

Answer 19

Bear raccoon coyote mink other canids

Question 20

What agent does Nanophyetus salmincola vector and what is the associated disease

Answer 20

Nerickettsia helminthoeca

Mostly fatal diarrhea and vomiting in dogs

Question 21

What fish are sources of Nanophyetus salmincola

Answer 21

Rainbow trout and steelhead trout

Question 22

What is the common name for Clonorchis sinensis

Answer 22

Oriental liver fluke

Question 23

What are common vertebrate hosts of the oriental liver fluke

Answer 23

People in Asia, dogs

Question 24

What is the vertebrate host of metorchis conjunctus

Answer 24

Cat, in bile duct

Question 25

How is platynosum fastosum transmitted | What are the host and specific site within the host

Answer 25

Ingestion of lizards or frogs | Found I bile ducts or gall bladder of cats in the tropics

Question 26

Alaria species are transmitted via various paratenic hosts. What are their vertebrate final hosts

Answer 26

Fox, raccoon, skunk, dog, cat | Live in intestine

Question 27

What is another way to transmit Alaria besides ingestion of paratenic host

Answer 27

Passed through milk of cat

Question 28

What stage of Alaria causes disease

Answer 28

Larva

Question 29

How are hosts infected with schistosomatidae

Answer 29

Skin penetration

Question 30

What does the name schistosomes imply?

Answer 30

Split bodies,... Separate males and females

Question 31

What is the scientific name for the America schistosomes and how does it cause disease

Answer 31

Heterobilharzia americana | Adults live in veins but, Eggs carried to liver causing fibrosis

Question 32

Why use saline when looking for the human parasite, Schistosoma mansoni

Answer 32

Eggs spontaneously hatch in fresh water and would no longer float

Question 33

Distinguishing feature of Schistosomes cercariae

Answer 33

Forked tail

Question 34

What causes death in Schistosoma japonicum infection in sheep

Answer 34

Huge liver and spleen cause esophageal vertices to rupture

Question 35

Which schistosomes cause zoonotic schistosomes dermatitis

Answer 35

Avian schistosomes (via contaminated water)

Question 36

How are Cestoda characterized

Answer 36

``` No gut (no exceptions), Segmented, White, Live in small intestines as adults, Hermaphroditic, anterior holdfast of some sort, lay eggs that are passed in feces of final host, Final host i Infected by eating larva in intermediate host ```

Question 37

Are segments of tapeworms older or youngest just behind the scolex

Answer 37

Youngest

Question 38

What does each pro glottis of Cestoda usually have

Answer 38

``` Genital opening(s) Both male and female reproductive parts ```

Question 39

Distinguish between the two types of tapeworms

Answer 39

Anapolyitic - segments release eggs into feces | Apolytic - segments detach and pass out with feces before releasing eggs

Question 40

What are 2 types of intermediate hosts of Diphyllobothriidea tapeworms

Answer 40

Copepod and vertebrate

Question 41

What is scientific name for broad fish tapeworm | What does it parasitize

Answer 41

Diphyllobothriidium latum | Fish eating mammals

Question 42

Life cycle of Diphyllobothridium latum

Answer 42

Operculate egg in feces Out of egg comes coracidium Ingested by copepod and becomes procercoid After fish ingests copepod, becomes placeroid Eventually develops into adult

Question 43

Physical characteristics of Dyphillobothrium latum

Answer 43

No hooks or suckers on scolex, only small groove; medial uterus

Question 44

What disease is associates with Diphyllobothriidium latum

Answer 44

B12 deficiency in Scandinavian women

Question 45

What are the important host of Spirometra mansonoides | What is associated disease called

Answer 45

Final host is bobcat Can use mammalian paratenic hosts - potentially zoonotic Sparganosis

Question 46

Characterize scolex of Cyclophyllidea

Answer 46

4 suckers

Question 47

Key points about life cycle of Cyclophyllidia

Answer 47

Terrestrial, only 1 intermediate host

Question 48

What type if animal is the second host of Mesocestoides

Answer 48

Vertebrates, often dogs

Question 49

Common name for Dipylidium caninum

Answer 49

Flea tapeworm (a Cyclophyllidia)

Question 50

Where are adult DIPYLIDIUM found, how was it transmitted | How are eggs deposited

Answer 50

Dog and cat, ingestion of infected flea | - segments crawl out to deposit eggs

Question 51

Anoplocephalids are parasites of? | Intermediate hosts are?

Answer 51

Herbivores, typically not pathogenic | Free living arthropods

Question 52

Genus of anoplocephala in sheep and cattle

Answer 52

Monieza (species in cattle have square eggs)

Question 53

Which anoplocephala in horse and at what site

Answer 53

A. Magna in jejunum | A. Perfoliats at ileo-cecal junction (has really narrow segments)

Question 54

Describe final host, intermediate host, physical characteristics and geographic distribution of Thysanosoma actinoides

Answer 54

Sheep Booklice Fringed segments Western US

Question 55

``` Describe larval stages of Taeniid tapeworms Cystocercus Strobilocercus Coenurus Hydatid ```

Answer 55

Cyctocercus - one head per bladder Strobilocercus - one head per bladder, but has strobilization (segments) Coerunus - multiple heads per bladder Hydatid - thousands of heads per cyst (only Echinococcus)

Question 56

How long does it take for Taenia segment to be shed

Answer 56

2 months

Question 57

Canine Taenia species and their larval forms

Answer 57

T. Ovis - cysticercus in sheep T. Multiceps - coenurus in sheep T. Pisiformis - cysticercus in rabbit T. Serialis - coenurus in rabbit T. Hydantigena - cysticercus in ruminants Foxes: T. Crassiceps - cysticercus in rodents

Question 58

What is the feline Taenia species and their intermediate host

Answer 58

T. Taeniaeformis | Rats (strobilicercus)

Question 59

What are human Taenia species, larval type and intermediate host

Answer 59

Taenia sanginata - cysticercus in beef muscle T. Asiatica - cysticercus in swine T. Solium - cysticercus in pork and in people

Question 60

Distinguish between Taenia saginata and T. solium

Answer 60

T. Saginata scolex has no hooks or suckers, t. Solium has sucker and 2 rows of hooks. Pro glottis of T. Saginata has more uterine branching than t. solium

Question 61

Common name for Taenia asiatica

Answer 61

Pork liver tapeworm

Question 62

Echinococcus larval stage

Answer 62

Hydatid

Question 63

Two important Echinicoccus species in dogs

Answer 63

E. granulosus | E. multilocularis

Question 64

Where do Echinococcus granulosus larvae usually migrate within the cervid intermediate host to form the hydatid cyst How do the larva get into the int. host

Answer 64

Lungs Eggs released in canid feces are ingested by cervids and hatch into larva

Question 65

What is a protoscolex

Answer 65

Larval tapeworms that develop from the hydatid cyst

Question 66

Where to Echinococcus multilocularis hydatids usually develop

Answer 66

Lungs of rodents